tty.h 24 KB

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  1. #ifndef _LINUX_TTY_H
  2. #define _LINUX_TTY_H
  3. #include <linux/fs.h>
  4. #include <linux/major.h>
  5. #include <linux/termios.h>
  6. #include <linux/workqueue.h>
  7. #include <linux/tty_driver.h>
  8. #include <linux/tty_ldisc.h>
  9. #include <linux/mutex.h>
  10. #include <linux/tty_flags.h>
  11. #include <uapi/linux/tty.h>
  12. /*
  13. * (Note: the *_driver.minor_start values 1, 64, 128, 192 are
  14. * hardcoded at present.)
  15. */
  16. #define NR_UNIX98_PTY_DEFAULT 4096 /* Default maximum for Unix98 ptys */
  17. #define NR_UNIX98_PTY_RESERVE 1024 /* Default reserve for main devpts */
  18. #define NR_UNIX98_PTY_MAX (1 << MINORBITS) /* Absolute limit */
  19. /*
  20. * This character is the same as _POSIX_VDISABLE: it cannot be used as
  21. * a c_cc[] character, but indicates that a particular special character
  22. * isn't in use (eg VINTR has no character etc)
  23. */
  24. #define __DISABLED_CHAR '\0'
  25. struct tty_buffer {
  26. struct tty_buffer *next;
  27. char *char_buf_ptr;
  28. unsigned char *flag_buf_ptr;
  29. int used;
  30. int size;
  31. int commit;
  32. int read;
  33. /* Data points here */
  34. unsigned long data[0];
  35. };
  36. /*
  37. * We default to dicing tty buffer allocations to this many characters
  38. * in order to avoid multiple page allocations. We know the size of
  39. * tty_buffer itself but it must also be taken into account that the
  40. * the buffer is 256 byte aligned. See tty_buffer_find for the allocation
  41. * logic this must match
  42. */
  43. #define TTY_BUFFER_PAGE (((PAGE_SIZE - sizeof(struct tty_buffer)) / 2) & ~0xFF)
  44. struct tty_bufhead {
  45. struct work_struct work;
  46. spinlock_t lock;
  47. struct tty_buffer *head; /* Queue head */
  48. struct tty_buffer *tail; /* Active buffer */
  49. struct tty_buffer *free; /* Free queue head */
  50. int memory_used; /* Buffer space used excluding
  51. free queue */
  52. };
  53. /*
  54. * When a break, frame error, or parity error happens, these codes are
  55. * stuffed into the flags buffer.
  56. */
  57. #define TTY_NORMAL 0
  58. #define TTY_BREAK 1
  59. #define TTY_FRAME 2
  60. #define TTY_PARITY 3
  61. #define TTY_OVERRUN 4
  62. #define INTR_CHAR(tty) ((tty)->termios.c_cc[VINTR])
  63. #define QUIT_CHAR(tty) ((tty)->termios.c_cc[VQUIT])
  64. #define ERASE_CHAR(tty) ((tty)->termios.c_cc[VERASE])
  65. #define KILL_CHAR(tty) ((tty)->termios.c_cc[VKILL])
  66. #define EOF_CHAR(tty) ((tty)->termios.c_cc[VEOF])
  67. #define TIME_CHAR(tty) ((tty)->termios.c_cc[VTIME])
  68. #define MIN_CHAR(tty) ((tty)->termios.c_cc[VMIN])
  69. #define SWTC_CHAR(tty) ((tty)->termios.c_cc[VSWTC])
  70. #define START_CHAR(tty) ((tty)->termios.c_cc[VSTART])
  71. #define STOP_CHAR(tty) ((tty)->termios.c_cc[VSTOP])
  72. #define SUSP_CHAR(tty) ((tty)->termios.c_cc[VSUSP])
  73. #define EOL_CHAR(tty) ((tty)->termios.c_cc[VEOL])
  74. #define REPRINT_CHAR(tty) ((tty)->termios.c_cc[VREPRINT])
  75. #define DISCARD_CHAR(tty) ((tty)->termios.c_cc[VDISCARD])
  76. #define WERASE_CHAR(tty) ((tty)->termios.c_cc[VWERASE])
  77. #define LNEXT_CHAR(tty) ((tty)->termios.c_cc[VLNEXT])
  78. #define EOL2_CHAR(tty) ((tty)->termios.c_cc[VEOL2])
  79. #define _I_FLAG(tty, f) ((tty)->termios.c_iflag & (f))
  80. #define _O_FLAG(tty, f) ((tty)->termios.c_oflag & (f))
  81. #define _C_FLAG(tty, f) ((tty)->termios.c_cflag & (f))
  82. #define _L_FLAG(tty, f) ((tty)->termios.c_lflag & (f))
  83. #define I_IGNBRK(tty) _I_FLAG((tty), IGNBRK)
  84. #define I_BRKINT(tty) _I_FLAG((tty), BRKINT)
  85. #define I_IGNPAR(tty) _I_FLAG((tty), IGNPAR)
  86. #define I_PARMRK(tty) _I_FLAG((tty), PARMRK)
  87. #define I_INPCK(tty) _I_FLAG((tty), INPCK)
  88. #define I_ISTRIP(tty) _I_FLAG((tty), ISTRIP)
  89. #define I_INLCR(tty) _I_FLAG((tty), INLCR)
  90. #define I_IGNCR(tty) _I_FLAG((tty), IGNCR)
  91. #define I_ICRNL(tty) _I_FLAG((tty), ICRNL)
  92. #define I_IUCLC(tty) _I_FLAG((tty), IUCLC)
  93. #define I_IXON(tty) _I_FLAG((tty), IXON)
  94. #define I_IXANY(tty) _I_FLAG((tty), IXANY)
  95. #define I_IXOFF(tty) _I_FLAG((tty), IXOFF)
  96. #define I_IMAXBEL(tty) _I_FLAG((tty), IMAXBEL)
  97. #define I_IUTF8(tty) _I_FLAG((tty), IUTF8)
  98. #define O_OPOST(tty) _O_FLAG((tty), OPOST)
  99. #define O_OLCUC(tty) _O_FLAG((tty), OLCUC)
  100. #define O_ONLCR(tty) _O_FLAG((tty), ONLCR)
  101. #define O_OCRNL(tty) _O_FLAG((tty), OCRNL)
  102. #define O_ONOCR(tty) _O_FLAG((tty), ONOCR)
  103. #define O_ONLRET(tty) _O_FLAG((tty), ONLRET)
  104. #define O_OFILL(tty) _O_FLAG((tty), OFILL)
  105. #define O_OFDEL(tty) _O_FLAG((tty), OFDEL)
  106. #define O_NLDLY(tty) _O_FLAG((tty), NLDLY)
  107. #define O_CRDLY(tty) _O_FLAG((tty), CRDLY)
  108. #define O_TABDLY(tty) _O_FLAG((tty), TABDLY)
  109. #define O_BSDLY(tty) _O_FLAG((tty), BSDLY)
  110. #define O_VTDLY(tty) _O_FLAG((tty), VTDLY)
  111. #define O_FFDLY(tty) _O_FLAG((tty), FFDLY)
  112. #define C_BAUD(tty) _C_FLAG((tty), CBAUD)
  113. #define C_CSIZE(tty) _C_FLAG((tty), CSIZE)
  114. #define C_CSTOPB(tty) _C_FLAG((tty), CSTOPB)
  115. #define C_CREAD(tty) _C_FLAG((tty), CREAD)
  116. #define C_PARENB(tty) _C_FLAG((tty), PARENB)
  117. #define C_PARODD(tty) _C_FLAG((tty), PARODD)
  118. #define C_HUPCL(tty) _C_FLAG((tty), HUPCL)
  119. #define C_CLOCAL(tty) _C_FLAG((tty), CLOCAL)
  120. #define C_CIBAUD(tty) _C_FLAG((tty), CIBAUD)
  121. #define C_CRTSCTS(tty) _C_FLAG((tty), CRTSCTS)
  122. #define L_ISIG(tty) _L_FLAG((tty), ISIG)
  123. #define L_ICANON(tty) _L_FLAG((tty), ICANON)
  124. #define L_XCASE(tty) _L_FLAG((tty), XCASE)
  125. #define L_ECHO(tty) _L_FLAG((tty), ECHO)
  126. #define L_ECHOE(tty) _L_FLAG((tty), ECHOE)
  127. #define L_ECHOK(tty) _L_FLAG((tty), ECHOK)
  128. #define L_ECHONL(tty) _L_FLAG((tty), ECHONL)
  129. #define L_NOFLSH(tty) _L_FLAG((tty), NOFLSH)
  130. #define L_TOSTOP(tty) _L_FLAG((tty), TOSTOP)
  131. #define L_ECHOCTL(tty) _L_FLAG((tty), ECHOCTL)
  132. #define L_ECHOPRT(tty) _L_FLAG((tty), ECHOPRT)
  133. #define L_ECHOKE(tty) _L_FLAG((tty), ECHOKE)
  134. #define L_FLUSHO(tty) _L_FLAG((tty), FLUSHO)
  135. #define L_PENDIN(tty) _L_FLAG((tty), PENDIN)
  136. #define L_IEXTEN(tty) _L_FLAG((tty), IEXTEN)
  137. #define L_EXTPROC(tty) _L_FLAG((tty), EXTPROC)
  138. struct device;
  139. struct signal_struct;
  140. /*
  141. * Port level information. Each device keeps its own port level information
  142. * so provide a common structure for those ports wanting to use common support
  143. * routines.
  144. *
  145. * The tty port has a different lifetime to the tty so must be kept apart.
  146. * In addition be careful as tty -> port mappings are valid for the life
  147. * of the tty object but in many cases port -> tty mappings are valid only
  148. * until a hangup so don't use the wrong path.
  149. */
  150. struct tty_port;
  151. struct tty_port_operations {
  152. /* Return 1 if the carrier is raised */
  153. int (*carrier_raised)(struct tty_port *port);
  154. /* Control the DTR line */
  155. void (*dtr_rts)(struct tty_port *port, int raise);
  156. /* Called when the last close completes or a hangup finishes
  157. IFF the port was initialized. Do not use to free resources. Called
  158. under the port mutex to serialize against activate/shutdowns */
  159. void (*shutdown)(struct tty_port *port);
  160. void (*drop)(struct tty_port *port);
  161. /* Called under the port mutex from tty_port_open, serialized using
  162. the port mutex */
  163. /* FIXME: long term getting the tty argument *out* of this would be
  164. good for consoles */
  165. int (*activate)(struct tty_port *port, struct tty_struct *tty);
  166. /* Called on the final put of a port */
  167. void (*destruct)(struct tty_port *port);
  168. };
  169. struct tty_port {
  170. struct tty_struct *tty; /* Back pointer */
  171. const struct tty_port_operations *ops; /* Port operations */
  172. spinlock_t lock; /* Lock protecting tty field */
  173. int blocked_open; /* Waiting to open */
  174. int count; /* Usage count */
  175. wait_queue_head_t open_wait; /* Open waiters */
  176. wait_queue_head_t close_wait; /* Close waiters */
  177. wait_queue_head_t delta_msr_wait; /* Modem status change */
  178. unsigned long flags; /* TTY flags ASY_*/
  179. unsigned char console:1; /* port is a console */
  180. struct mutex mutex; /* Locking */
  181. struct mutex buf_mutex; /* Buffer alloc lock */
  182. unsigned char *xmit_buf; /* Optional buffer */
  183. unsigned int close_delay; /* Close port delay */
  184. unsigned int closing_wait; /* Delay for output */
  185. int drain_delay; /* Set to zero if no pure time
  186. based drain is needed else
  187. set to size of fifo */
  188. struct kref kref; /* Ref counter */
  189. };
  190. /*
  191. * Where all of the state associated with a tty is kept while the tty
  192. * is open. Since the termios state should be kept even if the tty
  193. * has been closed --- for things like the baud rate, etc --- it is
  194. * not stored here, but rather a pointer to the real state is stored
  195. * here. Possible the winsize structure should have the same
  196. * treatment, but (1) the default 80x24 is usually right and (2) it's
  197. * most often used by a windowing system, which will set the correct
  198. * size each time the window is created or resized anyway.
  199. * - TYT, 9/14/92
  200. */
  201. struct tty_operations;
  202. struct tty_struct {
  203. int magic;
  204. struct kref kref;
  205. struct device *dev;
  206. struct tty_driver *driver;
  207. const struct tty_operations *ops;
  208. int index;
  209. /* Protects ldisc changes: Lock tty not pty */
  210. struct mutex ldisc_mutex;
  211. struct tty_ldisc *ldisc;
  212. struct mutex legacy_mutex;
  213. struct mutex termios_mutex;
  214. spinlock_t ctrl_lock;
  215. /* Termios values are protected by the termios mutex */
  216. struct ktermios termios, termios_locked;
  217. struct termiox *termiox; /* May be NULL for unsupported */
  218. char name[64];
  219. struct pid *pgrp; /* Protected by ctrl lock */
  220. struct pid *session;
  221. unsigned long flags;
  222. int count;
  223. struct winsize winsize; /* termios mutex */
  224. unsigned char stopped:1, hw_stopped:1, flow_stopped:1, packet:1;
  225. unsigned char low_latency:1, warned:1;
  226. unsigned char ctrl_status; /* ctrl_lock */
  227. unsigned int receive_room; /* Bytes free for queue */
  228. struct tty_struct *link;
  229. struct fasync_struct *fasync;
  230. struct tty_bufhead buf; /* Locked internally */
  231. int alt_speed; /* For magic substitution of 38400 bps */
  232. wait_queue_head_t write_wait;
  233. wait_queue_head_t read_wait;
  234. struct work_struct hangup_work;
  235. void *disc_data;
  236. void *driver_data;
  237. struct list_head tty_files;
  238. #define N_TTY_BUF_SIZE 4096
  239. /*
  240. * The following is data for the N_TTY line discipline. For
  241. * historical reasons, this is included in the tty structure.
  242. * Mostly locked by the BKL.
  243. */
  244. unsigned char closing:1;
  245. unsigned short minimum_to_wake;
  246. unsigned long process_char_map[256/(8*sizeof(unsigned long))];
  247. char *read_buf;
  248. int read_head;
  249. int read_tail;
  250. int read_cnt;
  251. unsigned long read_flags[N_TTY_BUF_SIZE/(8*sizeof(unsigned long))];
  252. unsigned char *echo_buf;
  253. unsigned int echo_pos;
  254. unsigned int echo_cnt;
  255. int canon_data;
  256. unsigned long canon_head;
  257. unsigned int canon_column;
  258. struct mutex atomic_read_lock;
  259. struct mutex atomic_write_lock;
  260. struct mutex output_lock;
  261. struct mutex echo_lock;
  262. unsigned char *write_buf;
  263. int write_cnt;
  264. spinlock_t read_lock;
  265. /* If the tty has a pending do_SAK, queue it here - akpm */
  266. struct work_struct SAK_work;
  267. struct tty_port *port;
  268. };
  269. /* Each of a tty's open files has private_data pointing to tty_file_private */
  270. struct tty_file_private {
  271. struct tty_struct *tty;
  272. struct file *file;
  273. struct list_head list;
  274. };
  275. /* tty magic number */
  276. #define TTY_MAGIC 0x5401
  277. /*
  278. * These bits are used in the flags field of the tty structure.
  279. *
  280. * So that interrupts won't be able to mess up the queues,
  281. * copy_to_cooked must be atomic with respect to itself, as must
  282. * tty->write. Thus, you must use the inline functions set_bit() and
  283. * clear_bit() to make things atomic.
  284. */
  285. #define TTY_THROTTLED 0 /* Call unthrottle() at threshold min */
  286. #define TTY_IO_ERROR 1 /* Cause an I/O error (may be no ldisc too) */
  287. #define TTY_OTHER_CLOSED 2 /* Other side (if any) has closed */
  288. #define TTY_EXCLUSIVE 3 /* Exclusive open mode */
  289. #define TTY_DEBUG 4 /* Debugging */
  290. #define TTY_DO_WRITE_WAKEUP 5 /* Call write_wakeup after queuing new */
  291. #define TTY_PUSH 6 /* n_tty private */
  292. #define TTY_CLOSING 7 /* ->close() in progress */
  293. #define TTY_LDISC 9 /* Line discipline attached */
  294. #define TTY_LDISC_CHANGING 10 /* Line discipline changing */
  295. #define TTY_LDISC_OPEN 11 /* Line discipline is open */
  296. #define TTY_HW_COOK_OUT 14 /* Hardware can do output cooking */
  297. #define TTY_HW_COOK_IN 15 /* Hardware can do input cooking */
  298. #define TTY_PTY_LOCK 16 /* pty private */
  299. #define TTY_NO_WRITE_SPLIT 17 /* Preserve write boundaries to driver */
  300. #define TTY_HUPPED 18 /* Post driver->hangup() */
  301. #define TTY_FLUSHING 19 /* Flushing to ldisc in progress */
  302. #define TTY_FLUSHPENDING 20 /* Queued buffer flush pending */
  303. #define TTY_HUPPING 21 /* ->hangup() in progress */
  304. #define TTY_WRITE_FLUSH(tty) tty_write_flush((tty))
  305. extern void tty_write_flush(struct tty_struct *);
  306. extern struct ktermios tty_std_termios;
  307. extern void console_init(void);
  308. extern int vcs_init(void);
  309. extern struct class *tty_class;
  310. /**
  311. * tty_kref_get - get a tty reference
  312. * @tty: tty device
  313. *
  314. * Return a new reference to a tty object. The caller must hold
  315. * sufficient locks/counts to ensure that their existing reference cannot
  316. * go away
  317. */
  318. static inline struct tty_struct *tty_kref_get(struct tty_struct *tty)
  319. {
  320. if (tty)
  321. kref_get(&tty->kref);
  322. return tty;
  323. }
  324. extern void tty_kref_put(struct tty_struct *tty);
  325. extern int tty_paranoia_check(struct tty_struct *tty, struct inode *inode,
  326. const char *routine);
  327. extern char *tty_name(struct tty_struct *tty, char *buf);
  328. extern void tty_wait_until_sent(struct tty_struct *tty, long timeout);
  329. extern int tty_check_change(struct tty_struct *tty);
  330. extern void stop_tty(struct tty_struct *tty);
  331. extern void start_tty(struct tty_struct *tty);
  332. extern int tty_register_driver(struct tty_driver *driver);
  333. extern int tty_unregister_driver(struct tty_driver *driver);
  334. extern struct device *tty_register_device(struct tty_driver *driver,
  335. unsigned index, struct device *dev);
  336. extern struct device *tty_register_device_attr(struct tty_driver *driver,
  337. unsigned index, struct device *device,
  338. void *drvdata,
  339. const struct attribute_group **attr_grp);
  340. extern void tty_unregister_device(struct tty_driver *driver, unsigned index);
  341. extern int tty_read_raw_data(struct tty_struct *tty, unsigned char *bufp,
  342. int buflen);
  343. extern void tty_write_message(struct tty_struct *tty, char *msg);
  344. extern int tty_put_char(struct tty_struct *tty, unsigned char c);
  345. extern int tty_chars_in_buffer(struct tty_struct *tty);
  346. extern int tty_write_room(struct tty_struct *tty);
  347. extern void tty_driver_flush_buffer(struct tty_struct *tty);
  348. extern void tty_throttle(struct tty_struct *tty);
  349. extern void tty_unthrottle(struct tty_struct *tty);
  350. extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws);
  351. extern void tty_driver_remove_tty(struct tty_driver *driver,
  352. struct tty_struct *tty);
  353. extern void tty_free_termios(struct tty_struct *tty);
  354. extern int is_current_pgrp_orphaned(void);
  355. extern struct pid *tty_get_pgrp(struct tty_struct *tty);
  356. extern int is_ignored(int sig);
  357. extern int tty_signal(int sig, struct tty_struct *tty);
  358. extern void tty_hangup(struct tty_struct *tty);
  359. extern void tty_vhangup(struct tty_struct *tty);
  360. extern void tty_vhangup_locked(struct tty_struct *tty);
  361. extern void tty_vhangup_self(void);
  362. extern void tty_unhangup(struct file *filp);
  363. extern int tty_hung_up_p(struct file *filp);
  364. extern void do_SAK(struct tty_struct *tty);
  365. extern void __do_SAK(struct tty_struct *tty);
  366. extern void disassociate_ctty(int priv);
  367. extern void no_tty(void);
  368. extern void tty_flip_buffer_push(struct tty_struct *tty);
  369. extern void tty_flush_to_ldisc(struct tty_struct *tty);
  370. extern void tty_buffer_free_all(struct tty_struct *tty);
  371. extern void tty_buffer_flush(struct tty_struct *tty);
  372. extern void tty_buffer_init(struct tty_struct *tty);
  373. extern speed_t tty_get_baud_rate(struct tty_struct *tty);
  374. extern speed_t tty_termios_baud_rate(struct ktermios *termios);
  375. extern speed_t tty_termios_input_baud_rate(struct ktermios *termios);
  376. extern void tty_termios_encode_baud_rate(struct ktermios *termios,
  377. speed_t ibaud, speed_t obaud);
  378. extern void tty_encode_baud_rate(struct tty_struct *tty,
  379. speed_t ibaud, speed_t obaud);
  380. extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old);
  381. extern int tty_termios_hw_change(struct ktermios *a, struct ktermios *b);
  382. extern int tty_set_termios(struct tty_struct *tty, struct ktermios *kt);
  383. extern struct tty_ldisc *tty_ldisc_ref(struct tty_struct *);
  384. extern void tty_ldisc_deref(struct tty_ldisc *);
  385. extern struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *);
  386. extern void tty_ldisc_hangup(struct tty_struct *tty);
  387. extern const struct file_operations tty_ldiscs_proc_fops;
  388. extern void tty_wakeup(struct tty_struct *tty);
  389. extern void tty_ldisc_flush(struct tty_struct *tty);
  390. extern long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
  391. extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file,
  392. unsigned int cmd, unsigned long arg);
  393. extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg);
  394. extern dev_t tty_devnum(struct tty_struct *tty);
  395. extern void proc_clear_tty(struct task_struct *p);
  396. extern struct tty_struct *get_current_tty(void);
  397. extern void tty_default_fops(struct file_operations *fops);
  398. extern struct tty_struct *alloc_tty_struct(void);
  399. extern int tty_alloc_file(struct file *file);
  400. extern void tty_add_file(struct tty_struct *tty, struct file *file);
  401. extern void tty_free_file(struct file *file);
  402. extern void free_tty_struct(struct tty_struct *tty);
  403. extern void initialize_tty_struct(struct tty_struct *tty,
  404. struct tty_driver *driver, int idx);
  405. extern void deinitialize_tty_struct(struct tty_struct *tty);
  406. extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx);
  407. extern int tty_release(struct inode *inode, struct file *filp);
  408. extern int tty_init_termios(struct tty_struct *tty);
  409. extern int tty_standard_install(struct tty_driver *driver,
  410. struct tty_struct *tty);
  411. extern struct tty_struct *tty_pair_get_tty(struct tty_struct *tty);
  412. extern struct tty_struct *tty_pair_get_pty(struct tty_struct *tty);
  413. extern struct mutex tty_mutex;
  414. extern spinlock_t tty_files_lock;
  415. extern void tty_write_unlock(struct tty_struct *tty);
  416. extern int tty_write_lock(struct tty_struct *tty, int ndelay);
  417. #define tty_is_writelocked(tty) (mutex_is_locked(&tty->atomic_write_lock))
  418. extern void tty_port_init(struct tty_port *port);
  419. extern void tty_port_link_device(struct tty_port *port,
  420. struct tty_driver *driver, unsigned index);
  421. extern struct device *tty_port_register_device(struct tty_port *port,
  422. struct tty_driver *driver, unsigned index,
  423. struct device *device);
  424. extern struct device *tty_port_register_device_attr(struct tty_port *port,
  425. struct tty_driver *driver, unsigned index,
  426. struct device *device, void *drvdata,
  427. const struct attribute_group **attr_grp);
  428. extern int tty_port_alloc_xmit_buf(struct tty_port *port);
  429. extern void tty_port_free_xmit_buf(struct tty_port *port);
  430. extern void tty_port_put(struct tty_port *port);
  431. static inline struct tty_port *tty_port_get(struct tty_port *port)
  432. {
  433. if (port)
  434. kref_get(&port->kref);
  435. return port;
  436. }
  437. /* If the cts flow control is enabled, return true. */
  438. static inline bool tty_port_cts_enabled(struct tty_port *port)
  439. {
  440. return port->flags & ASYNC_CTS_FLOW;
  441. }
  442. extern struct tty_struct *tty_port_tty_get(struct tty_port *port);
  443. extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty);
  444. extern int tty_port_carrier_raised(struct tty_port *port);
  445. extern void tty_port_raise_dtr_rts(struct tty_port *port);
  446. extern void tty_port_lower_dtr_rts(struct tty_port *port);
  447. extern void tty_port_hangup(struct tty_port *port);
  448. extern int tty_port_block_til_ready(struct tty_port *port,
  449. struct tty_struct *tty, struct file *filp);
  450. extern int tty_port_close_start(struct tty_port *port,
  451. struct tty_struct *tty, struct file *filp);
  452. extern void tty_port_close_end(struct tty_port *port, struct tty_struct *tty);
  453. extern void tty_port_close(struct tty_port *port,
  454. struct tty_struct *tty, struct file *filp);
  455. extern int tty_port_install(struct tty_port *port, struct tty_driver *driver,
  456. struct tty_struct *tty);
  457. extern int tty_port_open(struct tty_port *port,
  458. struct tty_struct *tty, struct file *filp);
  459. static inline int tty_port_users(struct tty_port *port)
  460. {
  461. return port->count + port->blocked_open;
  462. }
  463. extern int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc);
  464. extern int tty_unregister_ldisc(int disc);
  465. extern int tty_set_ldisc(struct tty_struct *tty, int ldisc);
  466. extern int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty);
  467. extern void tty_ldisc_release(struct tty_struct *tty, struct tty_struct *o_tty);
  468. extern void tty_ldisc_init(struct tty_struct *tty);
  469. extern void tty_ldisc_deinit(struct tty_struct *tty);
  470. extern void tty_ldisc_begin(void);
  471. /* This last one is just for the tty layer internals and shouldn't be used elsewhere */
  472. extern void tty_ldisc_enable(struct tty_struct *tty);
  473. /* n_tty.c */
  474. extern struct tty_ldisc_ops tty_ldisc_N_TTY;
  475. extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops);
  476. /* tty_audit.c */
  477. #ifdef CONFIG_AUDIT
  478. extern void tty_audit_add_data(struct tty_struct *tty, unsigned char *data,
  479. size_t size, unsigned icanon);
  480. extern void tty_audit_exit(void);
  481. extern void tty_audit_fork(struct signal_struct *sig);
  482. extern void tty_audit_tiocsti(struct tty_struct *tty, char ch);
  483. extern void tty_audit_push(struct tty_struct *tty);
  484. extern int tty_audit_push_task(struct task_struct *tsk,
  485. kuid_t loginuid, u32 sessionid);
  486. #else
  487. static inline void tty_audit_add_data(struct tty_struct *tty,
  488. unsigned char *data, size_t size, unsigned icanon)
  489. {
  490. }
  491. static inline void tty_audit_tiocsti(struct tty_struct *tty, char ch)
  492. {
  493. }
  494. static inline void tty_audit_exit(void)
  495. {
  496. }
  497. static inline void tty_audit_fork(struct signal_struct *sig)
  498. {
  499. }
  500. static inline void tty_audit_push(struct tty_struct *tty)
  501. {
  502. }
  503. static inline int tty_audit_push_task(struct task_struct *tsk,
  504. kuid_t loginuid, u32 sessionid)
  505. {
  506. return 0;
  507. }
  508. #endif
  509. /* tty_io.c */
  510. extern int __init tty_init(void);
  511. /* tty_ioctl.c */
  512. extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file,
  513. unsigned int cmd, unsigned long arg);
  514. extern long n_tty_compat_ioctl_helper(struct tty_struct *tty, struct file *file,
  515. unsigned int cmd, unsigned long arg);
  516. /* serial.c */
  517. extern void serial_console_init(void);
  518. /* pcxx.c */
  519. extern int pcxe_open(struct tty_struct *tty, struct file *filp);
  520. /* vt.c */
  521. extern int vt_ioctl(struct tty_struct *tty,
  522. unsigned int cmd, unsigned long arg);
  523. extern long vt_compat_ioctl(struct tty_struct *tty,
  524. unsigned int cmd, unsigned long arg);
  525. /* tty_mutex.c */
  526. /* functions for preparation of BKL removal */
  527. extern void __lockfunc tty_lock(struct tty_struct *tty);
  528. extern void __lockfunc tty_unlock(struct tty_struct *tty);
  529. extern void __lockfunc tty_lock_pair(struct tty_struct *tty,
  530. struct tty_struct *tty2);
  531. extern void __lockfunc tty_unlock_pair(struct tty_struct *tty,
  532. struct tty_struct *tty2);
  533. /*
  534. * this shall be called only from where BTM is held (like close)
  535. *
  536. * We need this to ensure nobody waits for us to finish while we are waiting.
  537. * Without this we were encountering system stalls.
  538. *
  539. * This should be indeed removed with BTM removal later.
  540. *
  541. * Locking: BTM required. Nobody is allowed to hold port->mutex.
  542. */
  543. static inline void tty_wait_until_sent_from_close(struct tty_struct *tty,
  544. long timeout)
  545. {
  546. tty_unlock(tty); /* tty->ops->close holds the BTM, drop it while waiting */
  547. tty_wait_until_sent(tty, timeout);
  548. tty_lock(tty);
  549. }
  550. /*
  551. * wait_event_interruptible_tty -- wait for a condition with the tty lock held
  552. *
  553. * The condition we are waiting for might take a long time to
  554. * become true, or might depend on another thread taking the
  555. * BTM. In either case, we need to drop the BTM to guarantee
  556. * forward progress. This is a leftover from the conversion
  557. * from the BKL and should eventually get removed as the BTM
  558. * falls out of use.
  559. *
  560. * Do not use in new code.
  561. */
  562. #define wait_event_interruptible_tty(tty, wq, condition) \
  563. ({ \
  564. int __ret = 0; \
  565. if (!(condition)) { \
  566. __wait_event_interruptible_tty(tty, wq, condition, __ret); \
  567. } \
  568. __ret; \
  569. })
  570. #define __wait_event_interruptible_tty(tty, wq, condition, ret) \
  571. do { \
  572. DEFINE_WAIT(__wait); \
  573. \
  574. for (;;) { \
  575. prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \
  576. if (condition) \
  577. break; \
  578. if (!signal_pending(current)) { \
  579. tty_unlock(tty); \
  580. schedule(); \
  581. tty_lock(tty); \
  582. continue; \
  583. } \
  584. ret = -ERESTARTSYS; \
  585. break; \
  586. } \
  587. finish_wait(&wq, &__wait); \
  588. } while (0)
  589. #endif